The study is the result of a collaboration between Pieter Vanden Berghe, Jens C. Schwamborn, Mikko Airavaara, and Tomi Laurila, representing:
- Aalto University, Department of Electrical Engineering and Automation & Department of Chemistry and Materials Science (Finland)
- University of Helsinki, Faculty of Pharmacy & Neuroscience Center, HiLife (Finland)
- KU Leuven, Laboratory for Enteric NeuroScience (Belgium)
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg
A New Window Into Brain Chemistry
Brain-on-a-chip models—tiny, lab-grown networks of brain cells—are becoming essential tools for studying neurological diseases and testing new drugs. However, measuring what these brain cells are doing has been a major challenge. Traditional electrodes often stop working once brain cells grow directly on top of them or when recordings are performed in the nutrient-rich solutions required for cell survival.
The collaborators solved this problem by developing optically transparent, highly sensitive sensors that remain fully functional even with neurons cultured directly on their surface.
Detecting Dopamine at Tiny Concentrations
The new sensors can measure dopamine at nanomolar levels, meaning they can detect extremely small amounts of the neurotransmitter. For the first time, the team successfully recorded both spontaneous and stimulated dopamine release from primary mouse midbrain neurons—while the cells stayed in their natural culture medium.
This breakthrough offers an unprecedented look at how living neurons behave outside the body.
Fully Transparent for Advanced Imaging
Because the electrodes are transparent, scientists can use advanced microscopy techniques through the sensor itself. The team demonstrated that they could perform:
- fluorescence microscopy
- live-cell calcium imaging (which shows real-time cell activity)
This combination—seeing the cells and measuring their chemical output at the same time—opens the door to more detailed and accurate brain-on-a-chip studies than ever before.
Safe for Delicate Brain Cultures
The researchers also confirmed that the sensors are biocompatible. Using several analytical methods and highly sensitive in-vitro brain-on-a-chip models, they showed that neurons grow healthily on the transparent electrodes for extended periods.
A Breakthrough With Wide Impact
This collaborative achievement has exciting implications for neuroscience and drug discovery. The new technology can help:
- improve disease models for Parkinson’s and other dopamine-related disorders
- reduce the need for animal testing
- accelerate the development of new therapeutics
- enable more complex and realistic brain-on-a-chip systems
By merging advanced materials science with cutting-edge neurobiology, the international team has created a powerful tool that brings us closer to understanding—and eventually treating—brain diseases with greater precision.